1. Field of the Invention
The present invention relates to electrical resistance cooking and more particularly to a circuit detecting and interrupting the current at an optimum point in the cooking cycle.
2. Description of the Prior Art
This invention also relates to and the most pertinent prior patent is believed to be my U.S. Pat. No. 4,554,440 which discloses a housing containing a pair of electrodes underlying a third electrode for receiving a quantity of food stuff, such as ground meat, between the electrodes to be cooked by the electrical resistance of the food. A source of electrical energy is connected with the pair of electrodes to complete a circuit through the food and the third electrode.
When hamburger meat is cooked on the resistance cooking apparatus of the above named patent, the meat is believed to be sufficiently cooked at points on the cooking current curve between just before the current has peaked (rare) and to just after the current has peaked (well done) and has begun a decline typical of such meat cooking current. The above patent monitors the rate of change of the cooking current curve.
Chicken, although it has a current cooking curve similar to that of hamburger meat, is not considered to be "done" at or as it approaches the current peak nor just after the peak. The point on the cooking curve is further down the declining curve at a point approximately equaling 1/3 or 331/3% of the current peak. This point was determined by empirical data and may vary slightly from meat to meat.
The doneness detection circuit must not only detect when this point is reached and stop the cooking process, but must also be immune to sizable snap fluctuations in the cooking current common when cooking chicken. These fluctuations are caused by minor steam explosions in the meat generated by heat during the cooking process.
The circuit of this invention filters these transitory fluctuations and is responsive to the magnitude of the current through the food and discontinues the current at an optimum cooked condition of the food.